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DNA barcodes for species identification in the hyperdiverse ant genus Pheidole (Formicidae: Myrmicinae).

Ng'endo RN, Osiemo ZB, Brandl R - J. Insect Sci. (2013)

Bottom Line: However, few studies attempt to compare the results of these molecular studies with a more traditional species delineation approach based on morphological characters.Only one MOTU was successfully identified to species level using the CO1 sequences of Pheidole species already in the Genbank.The occurrence of distinct mitochondrial lineages within morphological species highlights groups for further detailed genetic and morphological studies, and therefore a pluralistic approach using several methods to understand the taxonomy of difficult lineages is advocated.

View Article: PubMed Central - PubMed

Affiliation: Department of Ecology, Animal Ecology Faculty of Biology Philipps-Universitaet Marburg, Karl-von-Frisch-Strasse 8, D-35032 Marburg, Germany. rossangendo@yahoo.com

ABSTRACT
DNA sequencing is increasingly being used to assist in species identification in order to overcome taxonomic impediment. However, few studies attempt to compare the results of these molecular studies with a more traditional species delineation approach based on morphological characters. Mitochondrial DNA Cytochrome oxidase subunit 1 (CO1) gene was sequenced, measuring 636 base pairs, from 47 ants of the genus Pheidole (Formicidae: Myrmicinae) collected in the Brazilian Atlantic Forest to test whether the morphology-based assignment of individuals into species is supported by DNA-based species delimitation. Twenty morphospecies were identified, whereas the barcoding analysis identified 19 Molecular Operational Taxonomic Units (MOTUs). Fifteen out of the 19 DNA-based clusters allocated, using sequence divergence thresholds of 2% and 3%, matched with morphospecies. Both thresholds yielded the same number of MOTUs. Only one MOTU was successfully identified to species level using the CO1 sequences of Pheidole species already in the Genbank. The average pairwise sequence divergence for all 47 sequences was 19%, ranging between 0-25%. In some cases, however, morphology and molecular based methods differed in their assignment of individuals to morphospecies or MOTUs. The occurrence of distinct mitochondrial lineages within morphological species highlights groups for further detailed genetic and morphological studies, and therefore a pluralistic approach using several methods to understand the taxonomy of difficult lineages is advocated.

Show MeSH
Distribution of pairwise distances of ant genus Pheidole calculated using Kimura two-parameter model (Kimura 1980) among (a) 47 Cytochrome oxidase 1 (CO 1) sequences from Rio Cachoeira Nature Reserve in Brazil and (b) 141 CO1 sequences from the Genbank. The 47 sequences have a peak near zero and another between 18% and 24%, while the 141 sequences have a major peak between 16% and 24% of sequence divergence. High quality figures are available online.
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f02_01: Distribution of pairwise distances of ant genus Pheidole calculated using Kimura two-parameter model (Kimura 1980) among (a) 47 Cytochrome oxidase 1 (CO 1) sequences from Rio Cachoeira Nature Reserve in Brazil and (b) 141 CO1 sequences from the Genbank. The 47 sequences have a peak near zero and another between 18% and 24%, while the 141 sequences have a major peak between 16% and 24% of sequence divergence. High quality figures are available online.

Mentions: This study produced a final aligned 636 bp fragment, characterized with no gaps for all the 47 sequences. Sequences were heavily AT biased (especially in the third codon position), as is expected in insect mitochondrial DNA (Crozier and Crozier 1993; Table 1). The average pairwise sequence divergence of all 47 sequences was 19%, ranging from 0–25% (Figure 2a). The distribution of Kimura two parameter distances for 47 sequences showed one peak near zero and another between 18 and 24%, while the 141 CO1 sequences from Genbank had a peak between 16 and 24% of sequence divergence (Figure 2b).


DNA barcodes for species identification in the hyperdiverse ant genus Pheidole (Formicidae: Myrmicinae).

Ng'endo RN, Osiemo ZB, Brandl R - J. Insect Sci. (2013)

Distribution of pairwise distances of ant genus Pheidole calculated using Kimura two-parameter model (Kimura 1980) among (a) 47 Cytochrome oxidase 1 (CO 1) sequences from Rio Cachoeira Nature Reserve in Brazil and (b) 141 CO1 sequences from the Genbank. The 47 sequences have a peak near zero and another between 18% and 24%, while the 141 sequences have a major peak between 16% and 24% of sequence divergence. High quality figures are available online.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3735075&req=5

f02_01: Distribution of pairwise distances of ant genus Pheidole calculated using Kimura two-parameter model (Kimura 1980) among (a) 47 Cytochrome oxidase 1 (CO 1) sequences from Rio Cachoeira Nature Reserve in Brazil and (b) 141 CO1 sequences from the Genbank. The 47 sequences have a peak near zero and another between 18% and 24%, while the 141 sequences have a major peak between 16% and 24% of sequence divergence. High quality figures are available online.
Mentions: This study produced a final aligned 636 bp fragment, characterized with no gaps for all the 47 sequences. Sequences were heavily AT biased (especially in the third codon position), as is expected in insect mitochondrial DNA (Crozier and Crozier 1993; Table 1). The average pairwise sequence divergence of all 47 sequences was 19%, ranging from 0–25% (Figure 2a). The distribution of Kimura two parameter distances for 47 sequences showed one peak near zero and another between 18 and 24%, while the 141 CO1 sequences from Genbank had a peak between 16 and 24% of sequence divergence (Figure 2b).

Bottom Line: However, few studies attempt to compare the results of these molecular studies with a more traditional species delineation approach based on morphological characters.Only one MOTU was successfully identified to species level using the CO1 sequences of Pheidole species already in the Genbank.The occurrence of distinct mitochondrial lineages within morphological species highlights groups for further detailed genetic and morphological studies, and therefore a pluralistic approach using several methods to understand the taxonomy of difficult lineages is advocated.

View Article: PubMed Central - PubMed

Affiliation: Department of Ecology, Animal Ecology Faculty of Biology Philipps-Universitaet Marburg, Karl-von-Frisch-Strasse 8, D-35032 Marburg, Germany. rossangendo@yahoo.com

ABSTRACT
DNA sequencing is increasingly being used to assist in species identification in order to overcome taxonomic impediment. However, few studies attempt to compare the results of these molecular studies with a more traditional species delineation approach based on morphological characters. Mitochondrial DNA Cytochrome oxidase subunit 1 (CO1) gene was sequenced, measuring 636 base pairs, from 47 ants of the genus Pheidole (Formicidae: Myrmicinae) collected in the Brazilian Atlantic Forest to test whether the morphology-based assignment of individuals into species is supported by DNA-based species delimitation. Twenty morphospecies were identified, whereas the barcoding analysis identified 19 Molecular Operational Taxonomic Units (MOTUs). Fifteen out of the 19 DNA-based clusters allocated, using sequence divergence thresholds of 2% and 3%, matched with morphospecies. Both thresholds yielded the same number of MOTUs. Only one MOTU was successfully identified to species level using the CO1 sequences of Pheidole species already in the Genbank. The average pairwise sequence divergence for all 47 sequences was 19%, ranging between 0-25%. In some cases, however, morphology and molecular based methods differed in their assignment of individuals to morphospecies or MOTUs. The occurrence of distinct mitochondrial lineages within morphological species highlights groups for further detailed genetic and morphological studies, and therefore a pluralistic approach using several methods to understand the taxonomy of difficult lineages is advocated.

Show MeSH